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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Allmäntandläkares beslut att avstå revisionsbehandling på en tidigare rotfylld tand med kvarstående apikal parodontit

Magnusson, Karin, Eriksen, Linnea January 2016 (has links)
Syftet var att med kvalitativ metodik analysera den process som föregår allmäntandläkares beslut att avstå revisionsbehandling på en tidigare rotfylld tand med kvarstående apikal parodontit. Fem allmäntandläkare valdes strategiskt ut på grundval av att tandläkaren inom de senaste tre månaderna fattat beslutet att avstå från revisionsbehandling av minst en tidigare rotfylld tand med kvarstående apikal parodontit. Urvalet syftade också till en variation av informanternas kön, ålder, utbildningsort, yrkeserfarenhet och offentlig/privat verksamhet. Fem semistrukturerade djupintervjuer utfördes om händelseförloppet mellan patient och tandläkare som resulterat i att tandläkaren valde att avstå från revisionsbehandling. Samtliga intervjuer dokumenterades med en digital bandspelare, transkriberades ordagrant och analyserades med kvalitativ innehållsanalys. Ett tema som åskådliggör det latenta innehållet identifierades: ”Pragmatisk avvägning mellan teori och verklighet” med två huvudkategorier. Den första var ”Balanserat utnyttjande av makt”, med subkategorierna ”Kunskap som maktfaktor”, ”Patientens behov som maktfaktor” och ”Maktinfluerad information”. Den andra huvudkategorin var ”Erfarenheten som beslutsstöd” med subkategorierna ”Ifrågasatt hälsovinst” och ”Uttalad aktiv strategi”. Beslutet att avstå revisionsbehandling på tand med kvarstående apikal parodontit innebar för informanterna en praktisk kliniskt fungerande balansgång mellan inlärd teori och den kliniska verkligheten. Beslutet fattades i ett sammanhang där patienten hade inflytande och där man tog hänsyn till den egna kliniska erfarenheten. / The aim was to analyse the process that precedes the general dentist's decision to waive retreatment of a previously root-filled tooth with persistent apical periodontitis, using a qualitative approach.Five general dentists were strategically selected according to during the past three months having made a decision to waive retreatment of at least one previously root-filled tooth with persistent apical periodontitis. The selection further aimed at a variation concerning gender, age, location of undergraduate education, work experience duration and service affiliation. Five semi-structured interviews were conducted on the events between patient and dentist that resulted in the dentist´s choice to waive retreatment. All interviews were digitally recorded, verbatim transcribed and analysed using qualitative content analysis.A theme illustrating the latent content was identified: “A pragmatic balance between theory and reality” with two main categories. The first was “A balanced utilization of authority”, with the subcategories “Expertise as power-factor”, “Patient´s needs as power-factor” and “Power-influenced information”. The second category was “Experience as support to decision”, with the subcategories “Disputed health improvement” and “Established active strategy”. For the informants, the decision to waive retreatment meant a practical clinically workable balance between the learned theoretical knowledge and clinical practice. This decision is made in a context where the patient had influence and where the dentists´ own clinical experience was taken into account.
2

Protein sorting to the apical membrane of epithelial cells / Proteinsortierung an die apikale Membran von Epithelzellen

Schuck, Sebastian 18 December 2004 (has links) (PDF)
The structure and functions of lipid rafts and the mechanisms of intracellular membrane trafficking are major topics in current cell biological research. Rafts have been proposed to act as sorting platforms during biosynthetic transport, especially along pathways that deliver proteins to the apical membrane of polarised cells. Based on this, the aim of this work was to contribute to the understanding of apical sorting in epithelial cells. The study of how lipid rafts are structured has been hampered by the scarcity of techniques for their purification. Rafts are thought to be partially resistant to solubilisation by mild detergents, which has made the isolation of detergent-resistant membranes (DRMs) the primary method to characterise them biochemically. While a growing number of detergents is being used to prepare DRMs, it is not clear what can be inferred about the native structure of cell membranes from the composition of different DRMs. This issue was addressed by an analysis of DRMs prepared with a variety of mild detergents. The protein and lipid content of different DRMs from two cell lines, Madin-Darby canine kidney (MDCK) and Jurkat cells, was compared. It was shown that the detergents differed considerably in their ability to selectively solubilise membrane proteins and lipids. These results make it unlikely that different DRMs reflect the same underlying principle of membrane organisation. Another obstacle for understanding apical sorting is that the evidence implicating certain proteins in this process has come from various disparate approaches. It would be helpful to re-examine the putative components of the apical sorting machinery in a single experimental system. To this end, a retroviral system for RNA interference (RNAi) in MDCK cells was established. Efficient suppression of thirteen genes was achieved by retroviral co-expression of short hairpin RNAs and a selectable marker. In addition, the system was extended to simultaneously target two genes, giving rise to double knockdowns.Retroviral RNAi was applied to deplete proteins implicated in apical sorting. Surprisingly, none of the knockdowns analysed caused defects in surface delivery of influenza virus hemagglutinin, a common marker protein for apical transport. Therefore, none of the proteins examined is absolutely required for transport to the apical membrane of MDCK cells. Cells may adapt to the depletion of proteins involved in membrane trafficking by activating alternative pathways. To avoid such adaptation, a visual transport assay was established. It is based on the adenoviral expression of fluorescent marker proteins whose surface transport can be followed microscopically as soon as RNAi has become effective. With this assay, it should now be possible to screen the knockdowns for defects in surface transport. Taken together, this work has provided a number of experimental tools for the study of membrane trafficking in epithelial cells. First, the biochemical analysis of DRMs highlighted that DRMs obtained with different detergents are unlikely to correspond to distinct types of membrane microdomains in cell membranes. Second, the retroviral RNAi system should be valuable for defining the function of proteins, not only in membrane transport, but also in processes like epithelial polarisation. Third, the visual assay for monitoring the surface transport of adenovirally expressed marker proteins should be suitable to detect defects in polarised sorting.
3

Jämförelse av global longitudinell strain mellan två ekokardiografiska mjukvaruprogram

Lam, Cecilia January 2020 (has links)
Idag är ekokardiografi den dominerande undersökningsmetoden för att studera hjärtat. Ekokardiografi kan med hjälp av ultraljud avbilda hjärtat utifrån olika projektioner som kan antingen sparas som stillbilder eller rörliga sekvenser. Ultraljud av hjärtat är en icke-invasiv teknik som kan utföras snabbt och orsakar därmed inget obehag för patienten. Global longitudinell strain (GLS) är ett vanligt mått inom ekokardiografi. GLS används allt oftare i kliniskt syfte för att bland annat följa behandlingsresultat och dessutom för tidig upptäckt av förändringar i myokardiet. Syftet med denna studie var att utreda om det fanns någon signifikant skillnad av mätvärden GLS mellan de två olika mjukvaruprogrammen, EchoPac och TomTec. I studien inkluderades 30 patienter, där sinusrytm och en god bildkvalité kunde erhållas. Mann-Whitney U test visade på en signifikant skillnad med P-värde 0,042. Bland-Altmandiagrammet visade på att alla värden, 30 totalt, förutom tre värden förhåller sig inom ett 95% konfidensintervall. Slutsatsen är att det finns en skillnad avseende GLS mellan de två mjukvaruprogrammen, utifrån denna studie. Analys av GLS hos samma patient bör utföras med samma mjukvaruprogram för att minimera variation av mätvärden så mycket som möjligt. / Echocardiography is today the dominant examination method for studying the heart. Echocardiography can with help of ultrasound provide an image of the heart from various projections that can either be saved as still images or moving sequences. Ultrasound of the heart is a non-invasive technique that can be performed quickly and thus causes no discomfort to the patient. Global longitudinal strain (GLS) is a common measure in echocardiography. GLS is increasingly used in clinical practice to monitor treatment outcome and to detect early changes in the myocardium. The purpose of this study was to determine if there were any significant difference in the measurement values of GLS between two different software programs, EchoPac and TomTec. The study included 30 patients with sinus rhythm and good image quality. The Mann-Whitney U test showed a significant difference of P 0.042. The Bland-Altman diagram showed that all values, 30 in total, except of three, are within a 95% confidence interval. The conclusion is that there is a difference of GLS between the two software programs, based on this study. Analysis of GLS in the same patient should be performed with the same software program to minimize measurement errors as much as possible.
4

Rotfyllningskvalitet vid endodontiska behandlingar på studentklinik med utgångspunkt från kliniska och röntgenologiska parametrar. / Quality of Root Canal Filling in Endodontic Treatments at Student Clinic Based on Clinical and Radiological Parameters.

Ahmad, Rashed, Nazir, Rahmani January 2023 (has links)
Syfte: Att granska hur väl indikatorbilden och rotfyllningsbilden överensstämmer utifrån mätningar med elektronisk apexlokalisator. Dessutom granskas om rotfyllningskvalitet är beroende av tandtyp och antal besök samt om det förekommer någon skillnad på behandlingsproceduren före eller under COVID-19 pandemin. Vidare granskas tecken på läkning i de fall där läkningsbild finns.  Material och metod: Totalt har 635 patienter fått endodontisk behandling på studentklinik för endodonti på Malmö Tandvårdshögskola under perioden 2016–2021. Av dessa uppfyllde 350 journaler inklusionskriterierna. Journaldata tillsammans med röntgenbilder granskades av två oberoende observatörer. Resultat: Av 350 tänder överensstämde 262 tänders indikatorbild och rotfyllningsbild med EAL-mätningar. Underkäksmolarer till följd av överkäksmolarer och överkäkpresmolarer som hade inadekvat rotfyllningskvalitet.  Cirka 70% av tänderna som behandlades färdigt krävde mellan 2–6 besök. Tecken på läkning kunde observeras hos 78 patienter (ca. 92 %) som följts med klinisk undersökning och läkningsbilder. Inga märkbara skillnader noterades i behandlingsproceduren före eller under Covid-19 pandemin. Slutsats: Rotfyllningarna uppvisade god kvalitet baserat på kliniskt och röntgenologiskt underlag. Studenterna behöver relativt många besök för att genomföra en endodontisk behandling. Behandlingen resulterar ofta i en rotfyllning som bedöms ha god kvalitet och så många fall läker. Det behövs ges tydligare rekommendationer till studenter gällande bestämning av arbetslängden och information om att EAL är mer pålitlig att fastställa arbetslängd. / Aim: To evaluate how well the working length radiograph and obturation radiograph corresponded with the working length (WL) measured initially by electronic apex locator (EAL). Furthermore, the aim of this study was to evaluate if the quality of root canal fillings was dependent on tooth type, number of dental visits and if there was any different in treatment procedure before and during the Covid-19 pandemic. Additionally, signs of healing were evaluated if radiographs were available.  Material and method: Patient journal and intraoral radiographs of 635 patients who had undergone endodontic treatment by students at the Faculty of Odontology at University of Malmö during 2016–2021 were evaluated. A total number of 350 patients fulfilled the inclusion’s criteria. Patient’s journal and radiographs were reviewed by two independent observers.  Results: Of 350 teeth, in 262 teeth working length radiograph and obturation radiograph was consistent with the working length determined by EAL. Mandibular morals followed by maxillary molars and premolars were tooth types that failed to keep WL measured by EAL. Approximately 70% teeth were treated between 2-6 visits. In 84 cases radiographs were available and signs of healing were observed in 78 cases (approx. 92%). No significant differences were observed in treatment procedure before and under the Covid-19 pandemic.   Conclusion: The root canal fillings were of good quality based on clinical and radiographic evidence. Students need more time to carry out endodontic treatment but, in most cases, root canal fillings were of good quality and periapical healing was obtained. Furthermore, the students need clearer recommendations regarding determination of WL.
5

Organization and formation of the apical membrane of epithelial cells / Organisation und Bildung der apikalen Membran von Epithelzellen

Meder, Doris 15 November 2004 (has links) (PDF)
Compartmentalization of cell membranes, in particular of the apical membrane of columnar epithelia, is the topic of this thesis. The first part characterizes the apical membrane and its specialized organization and morphology, whereas the second part focuses on the formation of this unique plasma membrane domain during epithelial polarization. The apical membrane of columnar epithelia is enriched in glycosphingolipids, a class of lipids that are known to interact with cholesterol to form liquid ordered domains, also termed "rafts", in cell membranes. Imaging the apical surface of untreated and raft lipid depleted MDCK cells with atomic force microscopy revealed that raft lipids are involved in the formation and/or maintenance of microvilli, actin based protrusions of the apical plasma membrane, indicating a regulatory link between membrane domains and the cytoskeleton. Furthermore, antibody patching and photobleaching experiments performed during the work of this thesis suggest that the organization into raft and non-raft domains is very different in the apical membrane of MDCK cells compared to the plasma membrane of a fibroblast. In fact, the data support the hypothesis that the apical membrane could be a percolating raft membrane in which rafts constitute the major phase and non-raft domains exist as isolated entities. The second part of this thesis analyses the segregation of apical and basolateral membrane domains during epithelial polarization. This segregation can either be achieved by generating scaffolded domains prior to junction formation or by polarized secretory and endocytic membrane traffic after the establishment of cell junctions. While most apical and basolateral marker proteins in MDCK cells follow the latter mechanism, this thesis reports that the apical marker gp135 is confined to the dorsal face already in single attached cells. The unknown antigen was purified and identified as podocalyxin. Analysis of a series of domain mutants revealed that the C-terminal PDZ-binding motif of podocalyxin is mainly responsible for its special localization, which it shares with the PDZ protein NHERF-2. Knocking down podocalyxin by RNA interference resulted in retardation of cell growth and epithelial polarization. Taken together, the data suggest that podocalyxin and NHERF-2 could be part of an early apical polarity scaffolding system based on PDZ-binding and PDZ-containing proteins.
6

Organization and formation of the apical membrane of epithelial cells

Meder, Doris 18 June 2004 (has links)
Compartmentalization of cell membranes, in particular of the apical membrane of columnar epithelia, is the topic of this thesis. The first part characterizes the apical membrane and its specialized organization and morphology, whereas the second part focuses on the formation of this unique plasma membrane domain during epithelial polarization. The apical membrane of columnar epithelia is enriched in glycosphingolipids, a class of lipids that are known to interact with cholesterol to form liquid ordered domains, also termed "rafts", in cell membranes. Imaging the apical surface of untreated and raft lipid depleted MDCK cells with atomic force microscopy revealed that raft lipids are involved in the formation and/or maintenance of microvilli, actin based protrusions of the apical plasma membrane, indicating a regulatory link between membrane domains and the cytoskeleton. Furthermore, antibody patching and photobleaching experiments performed during the work of this thesis suggest that the organization into raft and non-raft domains is very different in the apical membrane of MDCK cells compared to the plasma membrane of a fibroblast. In fact, the data support the hypothesis that the apical membrane could be a percolating raft membrane in which rafts constitute the major phase and non-raft domains exist as isolated entities. The second part of this thesis analyses the segregation of apical and basolateral membrane domains during epithelial polarization. This segregation can either be achieved by generating scaffolded domains prior to junction formation or by polarized secretory and endocytic membrane traffic after the establishment of cell junctions. While most apical and basolateral marker proteins in MDCK cells follow the latter mechanism, this thesis reports that the apical marker gp135 is confined to the dorsal face already in single attached cells. The unknown antigen was purified and identified as podocalyxin. Analysis of a series of domain mutants revealed that the C-terminal PDZ-binding motif of podocalyxin is mainly responsible for its special localization, which it shares with the PDZ protein NHERF-2. Knocking down podocalyxin by RNA interference resulted in retardation of cell growth and epithelial polarization. Taken together, the data suggest that podocalyxin and NHERF-2 could be part of an early apical polarity scaffolding system based on PDZ-binding and PDZ-containing proteins.
7

Protein sorting to the apical membrane of epithelial cells

Schuck, Sebastian 20 December 2004 (has links)
The structure and functions of lipid rafts and the mechanisms of intracellular membrane trafficking are major topics in current cell biological research. Rafts have been proposed to act as sorting platforms during biosynthetic transport, especially along pathways that deliver proteins to the apical membrane of polarised cells. Based on this, the aim of this work was to contribute to the understanding of apical sorting in epithelial cells. The study of how lipid rafts are structured has been hampered by the scarcity of techniques for their purification. Rafts are thought to be partially resistant to solubilisation by mild detergents, which has made the isolation of detergent-resistant membranes (DRMs) the primary method to characterise them biochemically. While a growing number of detergents is being used to prepare DRMs, it is not clear what can be inferred about the native structure of cell membranes from the composition of different DRMs. This issue was addressed by an analysis of DRMs prepared with a variety of mild detergents. The protein and lipid content of different DRMs from two cell lines, Madin-Darby canine kidney (MDCK) and Jurkat cells, was compared. It was shown that the detergents differed considerably in their ability to selectively solubilise membrane proteins and lipids. These results make it unlikely that different DRMs reflect the same underlying principle of membrane organisation. Another obstacle for understanding apical sorting is that the evidence implicating certain proteins in this process has come from various disparate approaches. It would be helpful to re-examine the putative components of the apical sorting machinery in a single experimental system. To this end, a retroviral system for RNA interference (RNAi) in MDCK cells was established. Efficient suppression of thirteen genes was achieved by retroviral co-expression of short hairpin RNAs and a selectable marker. In addition, the system was extended to simultaneously target two genes, giving rise to double knockdowns.Retroviral RNAi was applied to deplete proteins implicated in apical sorting. Surprisingly, none of the knockdowns analysed caused defects in surface delivery of influenza virus hemagglutinin, a common marker protein for apical transport. Therefore, none of the proteins examined is absolutely required for transport to the apical membrane of MDCK cells. Cells may adapt to the depletion of proteins involved in membrane trafficking by activating alternative pathways. To avoid such adaptation, a visual transport assay was established. It is based on the adenoviral expression of fluorescent marker proteins whose surface transport can be followed microscopically as soon as RNAi has become effective. With this assay, it should now be possible to screen the knockdowns for defects in surface transport. Taken together, this work has provided a number of experimental tools for the study of membrane trafficking in epithelial cells. First, the biochemical analysis of DRMs highlighted that DRMs obtained with different detergents are unlikely to correspond to distinct types of membrane microdomains in cell membranes. Second, the retroviral RNAi system should be valuable for defining the function of proteins, not only in membrane transport, but also in processes like epithelial polarisation. Third, the visual assay for monitoring the surface transport of adenovirally expressed marker proteins should be suitable to detect defects in polarised sorting.
8

Immunhistokemisk (IHC) analys av låggradigt inflammerade biopsier med apikal parodontit -en pilotstudie / Immunohistochemical (IHC) analysis of biopsies with apical periodontitis with assessed low-grade inflammation – a pilot study

Pesonen, Izabell, Ismail, Midia January 2021 (has links)
Syfte: Att ta reda på hur relationen ser ut för B- respektive T-lymfocyter i biopsier av rotfyllda tänder med apikal parodontit med bedömd låggradig inflammation. Denna studie kommer även att analysera hur den inflammatoriska bilden ser ut i förhållande till beskrivna symtom i dessa biopsier. Material & metod: En pilotstudie utfördes på 10 biopsier från rotfyllda tänder med apikal parodontit med bedömd låggradig inflammation enligt Danesh et al 2019 klassificeringssystem. Biopsierna hämtades från Malmö universitets biobank. Immunhistokemisk infärgning av antigenerna CD20+ och CD3+ utfördes samt analyserades med hjälp av digitalmikroskop. Jämförelsen av symtomen från remisserna skedde efter att de histologiska resultaten sammanställts. Resultat: Det fanns fler T-lymfocyter än B-lymfocyter i 6 stycken av biopsierna. I de resterande 4 biopsierna var de lika många. I remisserna hade symtombilden inte angetts föralla biopsier. Slutsats: Enligt vår pilotstudie ser vi tendenser till att T-lymfocyter är fler än B-lymfocyter eller att de är lika många. Inga slutsatser kunde dras gällande symtombilden. Ett större material från olika remittenter krävs för definitiva slutsatser. En vidare infärgning av CD4+ samt CD8+ skulle vara intressant. / Aim: To investigate the relation between B- and T- lymphocytes in biopsies of root-filled teeth with apical periodontitis with assessed low-grade inflammation. This study will also analyse what the inflammation looks like in relation to the symptoms described in these biopsies.  Study design: A pilot study was performed on 10 biopsies of root-filled teeth with apical periodontitis with assessed low-grade inflammation according to the classification system of Danesh et al 2019. The biopsies were collected from Malmö University's biobank. An immunohistochemical staining of antigens CD20+ and CD3+ were performed and analysed by a digital microscope. A comparison of the symptoms from the referrals were performed once the histological results were compiled. Results: There were more T-lymphocytes than B-lymphocytes in 6 of the biopsies. In the remaining 4 biopsies there were an equal amount of B- and T-lymphocytes. The symptoms were not stated for all biopsies in the referrals.  Conclusion: According to our pilot study, we see tendencies that T lymphocytes are more than B lymphocytes or that they are equal. No conclusions could be drawn regarding the symptom picture. Larger material from different referrers is required for definitive conclusions. A further staining of CD4 + and CD8 + would be interesting.
9

JÄMFÖRELSE AV VÄNSTER FÖRMAKSVOLYM I APIKAL TVÅKAMMARPROJEKTION, INSPELADE MED TVÅ OLIKA ULTRALJUDS GIVARE (S5-1 OCH X5-1)

Latifpour, Nasrin January 2018 (has links)
Abstrakt: Vänster förmaksstorlek har prognostisk betydelse inom kardiologi. Det finns generellt enighet om att vänster förmaksvolymmätning (VFV) är det bästa mätmåttet av vänster förmaksstorlek. För närvarande används S5-1 som är en phased array givare, som första val, för att avbilda 2-dimensionella två- och fyrkammarvyer. Matrix array givaren X5-1 är ett praktiskt kliniskt alternativ för insamling av samma 2D projektioner men den har inte utvärderats på ett adekvat sätt mot S5-1 givare avseende VFV. Syftet med studien är att undersöka om det föreligger någon statistisk signifikant skillnad vid bestämning av VFV i apikal tvåkammarvy beroende på val av givare. Studien omfattade 50 patienter som var remitterade för en ekokardografisk undersökning på avdelningen för klinisk fysiologi och nuklearmedicin på Skånes Universitetssjukhus i Malmö. Ekokardiografiska bilder, insamlades med båda givarna, från både patienter med normal och abnormal vänster förmaksstorlek som hade sinusrytm. VFV mättes med Simpsons biplanmetod efter gällande amerikanska och europeiska riktlinjer. Det fanns en signifikant korrelation mellan medelvärdet av VFV, mätta på bilder som erhållits med de två olika insamlingsmetoderna (r =0,98, P 0,0001). Den utförda Bland-Altmananalysen visade också en statistiskt signifikant överensstämmelse i VFV mätning mellan de två insamlingsmetoderna. Studien visade att X5-1 givaren kan vara ett praktiskt alternativ för att erhålla 2D tvåkammarprojektion på ett mer tidseffektivt sätt jämfört med S5-1 givaren. / Abstract: Left atrial size has a prognostic significance in cardiology.There is ecumenical agreement that measurement of left atrial volume (LAV) is the best way to evaluate the left atrial size. Currently, S5-1, a phased array transducer, is used as the first choice to depict the 2-dimensional (2D) two- and four apical chamber views. X5-1, a matrix array transducer, is a practical clinical option for collecting the same 2D projections, but it has not been adequately assessed against the S5-1 transducer with LAV in consideration. The purpose of the present study was to investigate whether there is any statistically significant difference in the determination of LAV in apical two chamber views depending on the choice of transducer. The study included 50 patients who were referred for an echocardiographic examination at the Department of Clinical Physiology and Nuclear Medicine at Skåne University Hospital in Malmö. Echocardiographic images collected with both transducers, from patients with both normal and abnormal left atrial sizes and with sinus rhythm. LAV was measured using Simpson's biplane method according to the current American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) guidelines. There was a significant correlation between the mean of LAV, measured in images obtained by the two different transducers (r = 0.98, P 0.0001). The Bland-Altman analysis showed a statistically significant agreement in LAV measurement between the two methods. The X5-1 transducer is possibly a practical alternative to obtain 2D apical two-chamber projection in a more time efficient manner compared to the S5-1 transducer.

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